Footwall refrigeration along a detachment fault: implications for the thermal evolution of core complexes

Oxygen isotope compositions of epidote and quartz from chloritic breccias that underlie the detachment fault in the metamorphic core complex of the Whipple Mountains yielded quartz-epidote fractionations that range from 4.1 to 6.4 per mil and increase systematically toward the fault. These fractionations give mean temperatures that decrease from approximately 432 degrees C at 50 meters below the fault to approximately 350 degrees C at 12 meters below the fault. This extreme thermal gradient of 82 degrees C over 38 meters (2160 degrees C per kilometer) is best explained by advective heat extraction by means of circulating surface-derived fluids. Models of lithospheric extension consider only conductive cooling resulting from tectonic denudation and thus require revision to include fluid-induced fault-zone refrigeration.     

Cloning and Characterization of Boar Epididymal Secretory Proteins by Homology to the Human

Northern blot analysis suggested that the boar epididymis produces closely related counterparts to human epididymal proteins HE1, HE3, HE4, HE5 and HE12. ‘Full‐length’ cloning by nucleic acid and amino acid sequence similarity was achieved by RT‐PCR methods in the case of the porcine counterparts of HE3 and HE4, while the homologues of HE5 and HE12, despite their cross‐hybridization during Northern blot analysis, have not yet been cloned. The two novel porcine cDNAs were derived from moderately abundant epididymal mRNAs that were 75 and 83% identical to HE3 and HE4 cDNAs, respectively. To emphasize their relationship to the corresponding HEs, they were named Se3 and Se4 cDNAs. Their open reading frames predicted small secretory proteins with 55% (Se3) and 76% (Se4) conserved amino acids. Monospecific antipeptide antibodies to HE secretory proteins identified He3‐ and HE12‐related proteins on Western blots of porcine epididymal fluid and semen. Both Northern and Western analyses indicated that the Se proteins were produced in a regionalized pattern and accumulated in the cauda fluid.     

Clearance of para-aminohippuric acid in wethers consuming locoweed

AIM: To validate the use of para-aminohippuric acid (PAH) as a marker for measuring blood flow in wethers consuming a mixed diet of locoweed and blue grama hay.

METHODS: Fourteen sheep, stratified by bodyweight (BW), were assigned to one of three treatments: 0.8 mg swainsonine (SW)/kg BW (HI), 0.2 mg SW/kg BW (LO), and no SW (Control). Sheep were fed various ratios of locoweed and blue grama hay to deliver SW treatments, for 28 days prior to infusion of PAH. Concentrations of SW and activities of alkaline phosphatase (Alk-P) and aspartate aminotransferase (AST) in serum were measured to confirm exposure to SW and subclinical intoxication. A single 20-ml injection of 5% PAH was delivered into the jugular vein after subclinical intoxication had been achieved. Blood samples were collected and serum analysed for PAH immediately prior to injection, then every 5 min from 5–30 min, and every 10 min from 30–60 min, following injection of PAH.

RESULTS: Effective delivery of SW was evident from the greater concentrations of SW measured in the serum of HI compared with LO animals (p<0.05). No significant differences were detected in the rate of elimination (range 0.097–0.108 L/min), elimination half-life (range 6.62–7.24 min), apparent volume of distribution for the central compartment (range 7.14–9.72 L), and clearance (range 0.73–0.92 L/min) of PAH, between treatments.

CONCLUSIONS: Subclinical intoxication with SW did not affect the pharmacokinetics of PAH. Thus, use of downstream dilution of PAH is a valid method to determine the rate of blood flow in nutrient flux experiments that involve consumption of locoweed.     

Effects of IGF‐1 on In Vitro Culture of Bovine Preantral Follicles are Dose‐Dependent

This study aimed at assessing the effect of different concentrations of the growth factor similar to insulin 1 (IGF‐1) in the development, survival and ultrastructure of the bovine preantral follicles cultured in situ. Fragments of bovine ovarian cortical tissue were cultured during 1 and 7 days in 1 ml of α‐MEM⁺, supplemented with different concentrations of human recombinant IGF‐1 (0, 30, 70 and 100 ng/ml), in an incubator at 37°C and 5% of CO₂ in 24‐well plates with total replacement of the medium every 2 days. Non‐cultured ovarian fragments (control) and ovarian fragments cultured during 1 and 7 days were processed for classic histology, mechanical isolation and electron transmission microscopy (ETM). Parameters such as normality, viability, activation, development, diameter and ultrastructure were evaluated. All statistical analyses were carried out using sas Version 9.2. The results showed that the percentage of follicles morphologically normal in the IGF‐1 30 ng/ml treatment was similar to the fresh control (p > 0.05) both on the day 1 and on the day 7 of in vitro culture. In the viability analysis, the cultured treatments maintained the percentage of viable follicles during the entire culture period (p > 0.05). After 7 days of culture, the IGF‐1 30 ng/ml treatment showed higher percentages of developing follicles (48.33%) than those of the fresh control (22.22%) and the cultured treatments (p < 0.05). Also, after 7 days of culture, IGF‐1 30 ng/ml presented a higher follicular diameter when compared to the control and other concentrations of IGF‐1 tested. Ultrastructurally, the non‐cultured control and IGF‐1 30 ng/ml, after 7 days of culture, showed conserved oocytes, nuclei and organelles. Hence, it is concluded that IGF‐1 30 ng/ml was the most efficient concentration for the development of bovine preantral follicles cultured in vitro.     

Chemical Usurpation of a Nest by Paper Wasp Parasites

The paper wasp Polistes atrimandibularis is an obligatory social parasite of another Polistes species, P. biglumis bimaculatus. To control the host nest, the parasite sequentially changes the composition of its chemical signature, the cuticular hydrocarbons, during the colonial cycle. Gas chromatography-mass spectrometry of the cuticular hydrocarbons at every stage of the cycle showed that the parasite can switch on and off an entire chemical family, namely, the unsaturated hydrocarbons. In this way the parasite can match the host signature at a critical moment of the colonial cycle.     

Role of Sperm Velocity Variables Associated with Poultry Breed in ‘Last Male Precedence’

It is well known that when a hen mates with multiple roosters, it is the sperm of the last male that usually fertilizes most of the eggs (‘last male precedence’). Sperm quality varies between males within a breed, but also between breeds, and thus, sperm competitiveness after mating may depend on the breeds of the roosters involved. The aim of the present work was to identify differences in sperm competitiveness between breeds, especially with respect to motility. A multibreed mating model was used. Blue Andaluza (BA) and Black Castellana (BC) hens left for 21 days with BA and BC roosters, respectively, were then left with Black‐barred Andaluza (Bb) roosters for another 21 days (experimental groups hBA‐rBC‐rBb and hBC‐rBA‐rBb). Bb roosters (as the second breed replacing the first) fertilized the majority of eggs in both the hBC‐rBA‐rBb and hBA‐rBC‐rBb groups. The percentage of offspring sired by BA roosters (8.0%) was higher (p < 0.05) than the percentage of chicks sired by BC roosters (2.1%). The fertility of the BC hens in the hBC‐rBA‐rBb group was higher (p < 0.01) than that of the BA hens in the hBA‐rBC‐rBb group. No difference in sperm concentration was seen between the breeds. Within the rapid sperm subpopulation (sperm velocity, >50 μm/s), Bb sperm showed a higher straight‐line velocity (VSL) and average path velocity (VAP) (p < 0.05) than BC sperm. The VSL and VAP values for Bb and BA sperm were similar. In conclusion, the present results show that the sperm of the BA breed, traditionally regarded as of moderate fertility, compensates for this drawback via sperm movement characteristics that afford it an advantage in competition scenarios involving males of other breeds. The VSL and VAP of the rapid sperm subpopulation may play the most important role in securing last male precedence.     

Fasciola hepatica infection in farmed emus (Dromaius novaehollandiae)

Objective To describe two cases of infection with Fasciola hepatica i n young farmed emus, subacute and chronic fasci-olosis and a response to treatment of the flock with albenda-zole.
Procedure Gross lesions were found at necropsy and hepatic lesions in microscopic examination. The parasite recovered from one emu was identified by its morphological characteristics and an egg count reduction test was carried out after treatment of the flock with albendazole.
Results Hepatic lesions resembling subacute and chronic fasciolosis of ruminants were identified. An adult fluke was recovered from the liver of one of the birds and was identified as F hepatica . The eggs of the fluke were irregular in shape and size. No fluke eggs were identifiable in faeces of live emus 10 days after treatment of the flock with albendazole at a dose of 10 mg/kg.
Conclusions This is the first reported case of infection with F hepatica i n farmed emus and the first report of the occurrence of Fasciola infection is the class Aves. The irregular shape and size of the eggs may be attributable to infection of an aberrant host. Treatment with albendazole eliminated eggs from the faeces of the flock.     

Calcium, calmodulin, and CaMKII requirement for initiation of centrosome duplication in Xenopus egg extracts

Aberrant centrosome duplication is observed in many tumor cells and may contribute to genomic instability through the formation of multipolar mitotic spindles. Cyclin-dependent kinase 2 (Cdk2) is required for multiple rounds of centrosome duplication in Xenopus egg extracts but not for the initial round of replication. Egg extracts undergo periodic oscillations in the level of free calcium. We show here that chelation of calcium in egg extracts or specific inactivation of calcium/calmodulin-dependent protein kinase II (CaMKII) blocks even initial centrosome duplication, whereas inactivation of Cdk2 does not. Duplication can be restored to inhibited extracts by addition of CaMKII and calmodulin. These results indicate that calcium, calmodulin, and CaMKII are required for an essential step in initiation of centrosome duplication. Our data suggest that calcium oscillations in the cell cycle may be linked to centrosome duplication.